This only ever occurs very rarely when there are local scripts listening for any W, A, S, D, or Spacebar inputs.
Every once in a while, it seems like these take/ replace the inputs for basic mobility (moving your character by default)
It’s just as weird/ cryptic as it sounds, and I’m sorry that I’m unable to provide more info; all I know is that this happened to me very few times in my most basic of games that just simply listen for/ detect basic movement button inputs. (WASD, Spacebar)
Players have been reporting being unable to jump, or moving left/ right/ forward/ backward and not being able to stop, or not being able to begin walking left/ right/ forward/ backward. They say reseting/ waiting a bit fixes the issue, but I assure you that outside of maybe the jumping, the rest are not issues generated by my own scripts. (I’ve seen this happen on multiple places of mine which listen for mouse.KeyButton1Down events detecting wasd/ spacebar.)